Setting up, using and looping through a list

Lists example from a Well House Consultants training course
More on Lists [link]

This example is described in the following article(s):
• Lots of ways of doing the same thing in Perl - list iteration - [link]

Source code: back Module: P208

# Setting up, using and looping through a list

@places = ("Melksham","Farnborough","Melksham","Westbury","Swindon");
# Here's an alternative - exactly the same thing!
@places = qw%Melksham Farnborough Melksham Westbury Swindon%;

print @places,"\n"; # print a list ("List context")
print "@places\n"; # Expand a list within a string ("Double Quote Context")
print @places+0,"\n"; # print a list length ("Scalar context")

print "Saturday in ",$places[3],"\n";
$places[2] = "Chippenham";
print "@places\n"; # Expand a list within a string ("Double Quote Context")
$places[5] = "Bradford-on-Avon";
print "@places\n"; # Expand a list within a string ("Double Quote Context")
push @places,"Trowbridge";

# ways of looping through a list

$p = 0;
while ($p < @places) {
        print "Have a ping for me in $places[$p]\n";
        $p++;
        }

$p = 0;
while ($p <= $#places) {
        print "Have a pint for me in $places[$p]\n";
        $p++;
        }

$p = 0;
while ($p < scalar(@places)) {
        print "Have a pee for me in $places[$p]\n";
        $p++;
        }

for ($p = 0; $p < scalar(@places); $p++) {
        print "Have a pie for me in $places[$p]\n";
        }

foreach $pl (@places) {
        print "Have a party for me in $pl\n";
        }

__END__

Sample output:

munchkin:q grahamellis$ perl back
MelkshamFarnboroughMelkshamWestburySwindon
Melksham Farnborough Melksham Westbury Swindon
5
Saturday in Westbury
Melksham Farnborough Chippenham Westbury Swindon
Melksham Farnborough Chippenham Westbury Swindon Bradford-on-Avon
Have a ping for me in Melksham
Have a ping for me in Farnborough
Have a ping for me in Chippenham
Have a ping for me in Westbury
Have a ping for me in Swindon
Have a ping for me in Bradford-on-Avon
Have a ping for me in Trowbridge
Have a pint for me in Melksham
Have a pint for me in Farnborough
Have a pint for me in Chippenham
Have a pint for me in Westbury
Have a pint for me in Swindon
Have a pint for me in Bradford-on-Avon
Have a pint for me in Trowbridge
Have a pee for me in Melksham
Have a pee for me in Farnborough
Have a pee for me in Chippenham
Have a pee for me in Westbury
Have a pee for me in Swindon
Have a pee for me in Bradford-on-Avon
Have a pee for me in Trowbridge
Have a pie for me in Melksham
Have a pie for me in Farnborough
Have a pie for me in Chippenham
Have a pie for me in Westbury
Have a pie for me in Swindon
Have a pie for me in Bradford-on-Avon
Have a pie for me in Trowbridge
Have a party for me in Melksham
Have a party for me in Farnborough
Have a party for me in Chippenham
Have a party for me in Westbury
Have a party for me in Swindon
Have a party for me in Bradford-on-Avon
Have a party for me in Trowbridge
munchkin:q grahamellis$

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This module and example are covered on the following public courses:
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